This invention relates to an outlet or non-return valve for a compressor, of the type comprising a valve seat having gas flow apertures or passages, a valve plate with valve closing spring tongues to cover and close the apertures, and a limit member which limits the lift of the valve plate.
In such outlet valves large through flow cross-sections can be obtained and the mass of the moving closing tongues can be kept relatively small, but with high delivery capacity the closing tongues cannot be prevented from a tendency to flutter and therefore to produce considerable noise, but more especially, from being subject to heavy stress on account of their high impact velocity.